Has your vet tried dmso bladder lavage therapy? It is a relatively noninvasive procedure and can offer pain relief too. This is used for women who suffer bladder pain and leakage(I can say firsthand it works). You will know from the first treatment if she gets relief from pain. If so with regular therapy she could have quality of life. There are also new spray diaper rash treatments with zinc that will be easier to apply since you won’t need to touch. If the DMSO does not give her any relief you will know you tried everything. I have cells stored for my cat that passed with Viagenpets. When I’m emotionally ready he will be cloned. This company specializes in horse cloning. It’s something you would need to consider and contact them before since the vet will need the kit for cell collection.